Flame Test Lab

The purpose of the lab was to demonstrate the colors of different chemicals emitted when the electrons of certain chemicals were burned and two chemicals were not revealed. Using the color recorded for each chemical, we were to infer the right chemical present.

Prelab Questions

Unknown 1- LiCl

Unknown 2- ZnCl

I knew the identity of the unknown because the color produced from the unknown got the same color as the chosen chemical tested.

Electron Configuration Battleship

July 28, 2015

The biggest challenge was attempting to utilize the skills we learned in class to verbally and mentally challenge our brains to electron configurate the elements in an organized fashion. I learned to list the electron configurate.

Mole-Mass Relationships Lab

         In this lab, the purpose of the lab was to use stoichiometry to find the percent yield of the solid product by first finding the theoretical yield of NaCl and plugging that in. 

         In this experiment, NaHCo3 and HCl was combined to form NaCl, CO2 and H2O. In order to achieve this, 2.04 grams were added to the evaporation dish and mixed with the acid HCl. Then to separate the H2O, the hot plate was used to evaporate the water and leave only the salt. 

1. NaCO3 is the limiting reactant because    there is a limited amount and is the only reactant not to be renewed. 

2. The theoretical yield of was 1.42 grams found by using proportions to cancel units out.

3. The mass of the remaining solid product after the evaporation of water is 1.38 found by subtracting 44.83 (mass of evaporating dish) from 46.31 (mass of e.d + remaining solid product).

4 The percent yield for this experiment is 97.2 found by dividing the actual yield (1.38) by the theoretical yield (1.42) times hundred. 

I believe the reason why our result was so close yet not exact was the way we were heating the products of the equation for. The more you heated it, the more water and grams fell. 

Composition of A Copper Sulfate Hydrate Lab

July 25, 2015

Composition of a Copper Sulfate Hydrate Lab

1. The mass of the hydrate used was 0.99 grams.

2. The mass of the water lost is 0.34 grams.

3. The percentage of water in the hydrate is 40%.

4. 11% was our percent error. Possible explanations for this error may have been inaccurate readings of the mass of the Copper Sulfate Hydrate or insufficient time to heat the substance.

5. 

a) 0.019 was the number of moles of water of water evaporated. 

b) 0.0041 was the number of CuSO4 remaining. 

c) 5 was the ratio of moles from CuSO4 to H20.

d) CuSO4 x 5H20 was the empirical formula.

My percent error was high and I believe that the coefficient for water is lower than the actual coefficient.

Mole Baggie Lab

July 24, 2015

Mole Baggie Lab

      In this lab, we were given two sets of bags one (A6) labeled with the number of molecules and another (B1) labeled with the number of grams. With this information, the Molar Mass was to be calculated. When the mass is calculated, there were five possible compounds that each baggie could be. There was sodium chloride, Potassium Sulfate, Zinc Oxide, Sodium Sulfate, and Calcium Carbonate.
      A6 ended up with a molar mass close to Sodium Sulfate. B1 resulted in the same possible compound as A6.
      To find the molar mass for A6, first the # of grams had to be found. The bag was first weighed and the weight of the bag was subtracted from the whole mass. Then the # of grams was divided by 0.045, which was the number of moles.
       To find the molar mass of B1, the number of grams were given and the number of moles had to found. For this, a conversion was needed to find to find the number of moles. After that the molar mass could be found. 

Double Replacement Reaction Lab

July 23, 2015

What surprised me the most was that the solution moved both in a liquid and solid way in the petri dish. I didn't expect the substance to be moving in gel like movements and it was very surprising in general.